550 width

Use the drop down menus below to select the height and depth required. A depth of 100mm is common for these saddles, but it's not unsual to see them deeper.

Note if the grilles to be installed will carry a damper you should avoid a 50mm deep saddle - the extra depth of the grille/damper combination will mean the damper will encroach into the main duct, restricting airflow.

Use the radio buttons to select flange type. A 25mm internal flange is usual on these saddles. Please note that this internal flange has the effect of reducing the duct size by 50mm; consideration therefore needs to be made when matching the grille to the saddle e.g. a 400x150 grille will require a 450x200 saddle. With a 20mm external flange this does not apply i.e. the grille size must match the duct size e.g. a 400x150 grille will require a 400x150 saddle.